1260845561 has 8 divisors (see below), whose sum is σ = 1278775944. Its totient is φ = 1242933120.

The previous prime is 1260845549. The next prime is 1260845563. The reversal of 1260845561 is 1655480621.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 105185536 + 1155660025 = 10256^2 + 33995^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1260845561 - 2⁶ = 1260845497 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1260845563) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 205835 + ... + 211871.

It is an arithmetic number, because the mean of its divisors is an integer number (159846993).

Almost surely, 2^1260845561 is an apocalyptic number.

It is an amenable number.

1260845561 is a deficient number, since it is larger than the sum of its proper divisors (17930383).

1260845561 is an equidigital number, since it uses as much as digits as its factorization.

1260845561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8971.

The product of its (nonzero) digits is 57600, while the sum is 38.

The square root of 1260845561 is about 35508.3871923240. The cubic root of 1260845561 is about 1080.3238514962.

The spelling of 1260845561 in words is "one billion, two hundred sixty million, eight hundred forty-five thousand, five hundred sixty-one".